|Budget Amount *help
¥2,000,000 (Direct Cost : ¥2,000,000)
Fiscal Year 1995 : ¥1,000,000 (Direct Cost : ¥1,000,000)
Fiscal Year 1994 : ¥1,000,000 (Direct Cost : ¥1,000,000)
Dopamine and serotonin metabolism in the rat brain (prefrontal cortex, nucleus accumbens, ventrolateral striatum, hypothalamus) were studied using in vivo microdialysis during rebound hyperphagia, (A) followed by 22 hour food deprivation, (B) induced by a time restricted feeding schedule, and (C) under the space restriction as a psychological stress. When female Wister rats were set free from the time restricted feeding schedule, daily food intake significantly increased. This rebound hyperphagia was further enhanced by adding a space restriction stress. Dopamine metabolism increased in the prefrontal cortex and nucleus accumbens of all groups, especially C group, of rats. Whereas dopamine metabolism in the striatum increased only in C group. In the hypothalamus, basal levels of dopamine was low and undetectable. Serotonin metabolism in the prefrontal cortex, increased in B group and further increased in C group. Whereas basal levels of serotonin was very low in nucleus accumbens, ventrolateral striatum, and hypothalamus, there was no significant difference among the 3 groups. These results suggest that eating behavior itself may be related to dopamine metabolism in prefrontal cortex and nucleus accumbens, and serotonin metabolism in prefrontal cortex, and rebound hyperphagia may be related serotonin metabolism in prefrontal cortex, and enhanced rebound hyperphagia under the space restriction stress may be related dopamine metabolism in prefrontal cortex and striatum, and serotonin metabolism in prefrontal cortex.